<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

/**
 * Doctrine_AuditLog_Listener
 *
 * @package     Doctrine
 * @subpackage  AuditLog
 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link        www.doctrine-project.org
 * @since       1.0
 * @version     $Revision$
 * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
 */
class Doctrine_AuditLog_Listener extends Doctrine_Record_Listener
{
	/**
	 * Instance of Doctrine_Auditlog
	 *
	 * @var Doctrine_AuditLog
	 */
	protected $_auditLog;

	/**
	 * Instantiate AuditLog listener and set the Doctrine_AuditLog instance to the class
	 *
	 * @param   Doctrine_AuditLog $auditLog
	 * @return  void
	 */
	public function __construct(Doctrine_AuditLog $auditLog)
	{
		$this->_auditLog = $auditLog;
	}

	/**
	 * Pre insert event hook for incrementing version number
	 *
	 * @param   Doctrine_Event $event
	 * @return  void
	 */
	public function preInsert(Doctrine_Event $event)
	{
		$version = $this->_auditLog->getOption('version');
		$name = $version['alias'] === null ? $version['name'] : $version['alias'];

		$record = $event->getInvoker();
		$record->set($name, $this->_getInitialVersion($record));
	}

	/**
	 * Post insert event hook which creates the new version record
	 * This will only insert a version record if the auditLog is enabled
	 *
	 * @param   Doctrine_Event $event
	 * @return  void
	 */
	public function postInsert(Doctrine_Event $event)
	{
		if ($this->_auditLog->getOption('auditLog')) {
			$class = $this->_auditLog->getOption('className');

			$record  = $event->getInvoker();
			$version = new $class();
			$version->merge($record->toArray(), false);
			$version->save();
		}
	}

	/**
	 * Pre delete event hook deletes all related versions
	 * This will only delete version records if the auditLog is enabled
	 *
	 * @param   Doctrine_Event $event
	 * @return  void
	 */
	public function preDelete(Doctrine_Event $event)
	{
		if ($this->_auditLog->getOption('auditLog')) {
			$className = $this->_auditLog->getOption('className');
			$version = $this->_auditLog->getOption('version');
			$name = $version['alias'] === null ? $version['name'] : $version['alias'];
			$event->getInvoker()->set($name, null);

			if ($this->_auditLog->getOption('deleteVersions')) {
				$q = Doctrine_Core::getTable($className)
				->createQuery('obj')
				->delete();
				foreach ((array) $this->_auditLog->getOption('table')->getIdentifier() as $id) {
					$conditions[] = 'obj.' . $id . ' = ?';
					$values[] = $event->getInvoker()->get($id);
				}

				$rows = $q->where(implode(' AND ', $conditions))
				->execute($values);
			}
		}
	}

	/**
	 * Pre update event hook for inserting new version record
	 * This will only insert a version record if the auditLog is enabled
	 *
	 * @param  Doctrine_Event $event
	 * @return void
	 */
	public function preUpdate(Doctrine_Event $event)
	{
		if ($this->_auditLog->getOption('auditLog')) {
			$class  = $this->_auditLog->getOption('className');
			$record = $event->getInvoker();

			$version = $this->_auditLog->getOption('version');
			$name = $version['alias'] === null ? $version['name'] : $version['alias'];

			$record->set($name, $this->_getNextVersion($record));

			$version = new $class();
			$version->merge($record->toArray(), false);
			$version->save();
		}
	}

	/**
	 * Get the initial version number for the audit log
	 *
	 * @param Doctrine_Record $record
	 * @return integer $initialVersion
	 */
	protected function _getInitialVersion(Doctrine_Record $record)
	{
		return 1;
	}

	/**
	 * Get the next version number for the audit log
	 *
	 * @param Doctrine_Record $record
	 * @return integer $nextVersion
	 */
	protected function _getNextVersion(Doctrine_Record $record)
	{
		if ($this->_auditLog->getOption('auditLog')) {
			return ($this->_auditLog->getMaxVersion($record) + 1);
		}
	}
}